The present invention is generally directed to integrated circuit packaging and more particularly to a method for packaging and identifying integrated circuits.
Standardization of integrated circuit packages provides advantages in electronics manufacturing. For example, standardized integrated circuit packages are easily handled by automated feed and placement equipment used to manufacture printed circuit board assemblies. Furthermore, technologies such as Tape Automated Bonding (TAB) take advantage of uniformity in the standardized packages to efficiently mount integrated circuits in the standardized packages.
Despite such advantages, there are also disadvantages to standardized packages. Because standardized packages have similar appearances, the identity of each integrated circuit contained within a respective package can become confused. Functionally different integrated circuits respectively mounted in identical standardized packages can be easily misidentified. If such misidentification takes place during assembly or repair, radically different integrated circuits can be accidently exchanged in an electronic assembly, resulting in costly damage to assembly components. For example, if the different integrated circuits are respectively mounted in packages having different designations for power and ground pins, it is likely that the integrated circuits would be damaged by power applied to the packages by the electronic assembly.
A previously known scheme to identify integrated circuits is to print identifying strings of alpha-numeric characters on a respective outer surface of each integrated circuit package, or to place a respective self adhesive label bearing such character strings on each package. Unfortunately such identification schemes are difficult to automate because machines often have difficulty reading the alpha-numeric characters. Another problem is that humans are prone to errors in reading printing or labels. Furthermore such schemes lack permanence since self adhesive labels can be accidentally rubbed off and printing can become smudged. What is needed is a reliable method for packaging and identifying integrated circuits that can be easily automated.